Year of Publication

2017

College

Public Health

Degree Name

Master of Public Health (M.P.H.)

Committee Chair

Steven Fleming, PhD

Committee Member

Erin Abner, MPH, PhD

Committee Member

Bin Huang, MS, DrPH

Abstract

Background and Objectives

Breast cancer has the highest incidence rates among women and is the second leading cause of death due to cancer in women. Of all breast cancers, triple negative breast cancer (TNBC) accounts for about one-fifth of breast cancer and tends to result in an aggressive form with larger tumors and rates of metastasis and is more frequently found in younger women. This results in an important need in information regarding the risk of diagnosis with triple negative breast cancer over other forms and covariates associated with death and TNBC. This paper studies the relationship between race, tobacco use, age, family history, marital status, insurance status, and menopausal status at diagnosis and the risk of mortality from TNBC.

Methods

Individual breast cancer patient data collected from the Kentucky Cancer Registry were analyzed to determine the association of potential risk factors with TNBC. The data was collected between 2009 and 2014 and contained individuals aged 18 or older that were diagnosed with breast cancer. Univariate and bivariate analysis were used to determine the characteristics of the study population. Logistic regression was used to determine the odds ratios for the covariates of interest in TNBC patients. Survival curves were used to compare survival for TNBC patients compared to all other breast cancer subtypes, and Cox proportional-hazard regression was used to determine the risk of death due to TNBC.

Results

Significant increases in the odds for death due to TNBC were seen with women who were widowed (OR 1.53; 95% CI: 1.01, 2.33), on Medicare (OR 2.90; 95% CI: 1.77, 4.74), uninsured (OR 3.84; 95% CI: 1.85, 8.00), or had a late stage at diagnosis (OR 9.462; 95% CI: 6.616, 13.531). These results are based on married women, privately insured women and women diagnosed at an early stage as the reference categories. There was a statistically significant difference between the survival curves for TNBC and all other subtypes (log-rank p < 0.0001) ; patients with TNBC had a lower probability of survival than those with other breast cancer subtypes. TNBC patients that were single (HR: 1.63 ; 95% CI: 1.06, 2.50), on Medicaid (HR: 1.81 ; 95% CI: 1.13, 2.88), on Medicare (HR: 2.73 ; 95% CI: 1.77, 4.20), uninsured (HR: 2.98 ; 95% CI: 1.57, 5.68), or diagnosed at a late stage (HR: 6.54; 95% CI: 5.03, 8.49) had a significantly higher hazard of death when compared wit h patients who were married, patients that were privately insured and patients that were diagnosed at an early stage .

Conclusions

The study results show that marital and insurance status may be related to an increase of death due to TNBC. The results support findings from previous studies as well as expand upon previous studies by separating based on breast cancer subtype. Overall, continued screening can help with early diagnosis and treatment. Because TNBC is an aggressive subtype, early diagnosis and treatment may help reduce the mortality rates associated with TNBC. Further research examining the covariates used in the study is needed to reinforce the results found in this study.

Included in

Public Health Commons

Share

COinS